Dark-blue-violet dye.



KARL SCHIRMACHER AND BERNHARD D IoKia, or HocHsr-oN-THEMAIN, GSERMIANQY, ASSIGNORS To raR wEaKE VORM. MEISTER LUCIUS & BRUNING, or HOCHST-ON- THE-MAIN, cERiLiNYjA CORPORATION OF GERMANY.

DARK-B LUE -VIOLET DYE.

Specification of Letters Patent.

Patented March 10,- 1908.

Application filed February 20, 1907. Serial No. 358,420.

many, have invented certain new and useful Improvements in Dark-Blue-Violet Dyes, of which the following is a specification.

This invention relates to new vat dyestuffs the constitution of which corresponds to the formula:

wherein R means ethyl and methyl.

The new dyestuffs may be obtained by oxidizing 5-alkyl-oxy-oxythionaphthene carboxylic acids (R :8 :C :2 :1) obtained from 5-alkyloxyphenylthioglyc ollicortho-carb oxylic acids -(RO:SCH CO()H:COOH= 5:2:1) by heating with alkali. They are violet powders, insoluble in water, soluble in hot alcohol, benzene, glacial acetic acid and chloroform with a violet color, in concentrated sulfuric acid with a green color. With alkaline hydrosulfite they yield yellow colored vats dyeing wool and cotton dark blue-violet shades.

The method to obtain the new dyestuffs is, for instance, as follows:

Example: 15.3 parts of aminophenolcarboXylic acid (OH:XH :COOH= 522:1 are boiled with 50 parts of glacial acetic acid for 12 hours in a reflux apparatus, half of the glacial acetic acid is then distilled and some water added. The acetylaminophenol carboxylic acid separates. It is obtained in a pure state by crystallizing' from water. Then 19,5 parts of this acid are dissolved in 20 parts of caustic soda-lye of 40 Be. and 200 parts of water, 15 parts of dimethylsulfate being added while stirring. After stirring for some hours, care being taken to keep the liquid alkaline, the methylation is complete; parts of caustic soda-lye of 40 B. specific gravity are then added and to effect hydrolysis the whole is boiled in a reflux apparatus till a test portion with hydroc hloric acid shows no more a precipitate of unchanged acetyl compound. 'hen cold it is acidified; there are then added 20 parts of hydrochloric acid of 20 Be. specific gravity and 6.9 parts of nitrite. The obtained and filtered diazo solution is run at 2025 (hintoa solution of 18 parts of potassium Xanthogenate and parts of sodium carbonate till no further nitrogen is evolved. Then are added 16 parts of sodium ohloracetate and 25 parts of caustic soda-lye of B. specific gravity and the whole is boiled. After 12 hours it is allowed to cool and on adding a mineral acid the 5 methoxyphenylthioglycollic ortho carboxylic acid (OCH :SCH COOH :COOH 5 :2 :1)

is preci itated. It is a yellowish powder difficult y soluble in cold Water crystalli'zing; from hot water in yellowish prisms of the melting point 198199.

To manufacture 5-1nethoXy-oxythionaphthene carboxylic acid 20 parts of 5-methoXyphenylthioglycollic ortho carboxylic acid are heated to 180-200 C. for some time with a mixture of 100 parts of caustic sogia and 10 parts of water. The fusion becomes yellow and gradually brittle. 'hen cold the mass is dissolved in water and by adding a mineral acid the 5-methoxyoxythionaphthene carboxylic acid is precipitated. It is soluble in acetates and a-lkalies, yielding, when treated with hydrochloric acid and nitrite, a nitroso compound crystallizing from water in reddish yellow needles. On boiling the afore described 5-1nethoxy-oxythionaphthene carboxylic acid with hydrochloric acid the 5- niethoxy-oxythionaphthene is obtained; it is volatile with steam and crystallizes in white needles.

To convert into the dyestuff, 23 parts'of 5- methoxy-oxythionaphthene carboxylic acid or 18 parts of 5-methoxy-oxythionaphthene and 22 parts of caustic soda-lye of 40 B. specific gravity are dissolved in 1000 parts of water and then is added a solution of potassium ferri cyanid till no further dyestufi' is formed. flakes, being, when dry, a violet-black powder. With an alkaline hydrosulfite solution it yields a vat from which itdyes wool. and cotton dark blue-violet tints. From the 5 methoxy oxythionaphthene carboxylic The dyestuif separates in violet acid a very like dyestuff may be obtained I As roduots the dyestnffs having the forum a:

inconcentrated sulfuric acid with a green.

'10 color with alkaline hydrosnlfite they yield yellow colored .vats dyeing wool and cotton dark blue-violet shades.

In testimony that we claim the foregoing as our invention,f.we have signed our names in presence of two subscribing witnesses.

KARL SOHIRMAOHER. BERNHARD DEICKE.

lVitnesses:

, JEAN GRUND, CARL GRUND. 

